2010 Volume 56 Issue 6 Pages 564-571
Background: Stenotic changes after stent implantation for coarctation of the aorta remain a major problem. There are only a few studies examining pathological vascular changes of the great arteries after stenting in the pediatric population. Aim: Using immunohistochemistry, we investigated the involvement of chronic inflammation in in-stent stenosis of abdominal great arteries after stent implantation in juvenile pigs. Methods: Five pigs, aged 4-5 weeks with body weights ranging from 8-10 kg, were used for this study. Stents were implanted in the abdominal great artery. Abdominal arteries with stents were later collected and stained with hematoxylin and eosin. Immunological staining was also performed for the intima, using vascular endothelial growth factor (VEGF), interleukin-8 (IL-8), cyclooxygenase 2 (COX-2) and peroxisome proliferators activated receptor gamma (PPARγ) antibodies. Results: Only one of five samples showed stenotic change due to neointimal proliferation. Neutrophil recruitment in the neointima was confirmed by H & E stain at the site of stenosis. VEGF, IL-8, COX-2 and PPARγ expressions in the neointima were also increased at the site of stent implantation compared with those in normal tissue. Conclusion: Our data suggest that chronic inflammation is involved in the pathogenesis of instent stenosis after stent implantation. Management of inflammation may be important toprevent stenotic change after stenting in pediatric cardiology.
